Electricity-meter.



PATENTED SEPT. 15. 1903.

L. J.-ARON. ELECTRICITY METER.

' APPLICATION nun rm. 6. 1903. no MODEL. mums-sum: 1,

five/liar WITNESSES No. 739,251. PATENTBDSEPT. 15, 1903.

L. J. ARON.

ELECTRICITY METER.

APPLICATION IILED FEB. 6. 1903.

no 101121.. a sums-4511mm 2.

Fig? ,9.

UNITED STATES Patented September 15, 1903.

PATENT OFF CE.

LEONARD JAMES ARON, OF BIRMINGHAM, ENGLAND, ASSIGNOR TO THE ELECTRIC AND ORDNANCE ACCESSORIES COMPANY, LIMITED, OF ASTON,

NEAR BIRMINGHAM, ENGLAND.

ELECTRICITY-M ETER.

SPECIFICATION forming part of Letters Patent No. 739,251, dated September 15, 1903.

Application filed February 6, 1903. Serial No. 142.219. (No model.)

To all whom it may concern:

Be it known that I, LEONARD JAMES Anon, electrical engineer, a subject of the King of Great Britain, residing at Stellite \Vorks,

5 Cheston Road, Aston, Birmingham, England,

have invented certain new and useful Improvements in Electricity-Meters, of which the following is a specification. v

This invention has relation to electricityl meters of the two-rate type in which the supply of current to the consumer is registered at two different rates of charge according to the particular time or part of the day during which the supply is taken.

I In ordinary two-rate meters the rate of registration is changed during any desired period and at any part of a day either by connecting and disconnecting resistances, which alter the registering rate of a single set of recording-dials, or by shifting certain connecting wheels so that registration is effected alternately on two different sets of recording dials, one set of which records the consumption during the normal or low-rate period of the day, while the other set records the consumption of current during the high-rate period. Hitherto it has been the practice to actuate the devices for changing over or varying the registration by a clock mechanism distinct from the meter mechanism and provided with two dials both driven so as to make one complete rotation every twenty-four hours, and such dial has been provided with separate adjustable arrangements, one set to act at the beginning and the other at the end of the high-rate period and adapted to operate the rate-changing devices at certain hours corresponding to the commencing and finishing times of the said period. I

0 Now one of the objects of the present invention (which has reference in particular to energy-meters of the well-known Aron or twoclock type) is to provide a two-rate meter working on the said Aron principle which shall be perfectly accurate in registering the supply during the two periods and yet be much simpler in construction and more durable and cheaper to make than the two-rate meters now in use, and another object is to provide simplified and improved adjustable devices whereby the duration and the times of commencement and finish of the high-rate period may be readily altered. These objects we propose to attain. by dispensing altogether with the separate rate-changing clock mechanism and its two dials and attendant sets of devices operating,respectively, at the beginning and the end of the high-rate period and by affecting the alteration in the registering action of the meter entirely by a single-dial ratechanging mechanism actuated off the ordinary normal time-clock of an Aron meter, the single dial of the said mechanism being provided with an arrangement of adjustable contacts whereby both the time of commencement and the duration of the high-rate period may be determined and altered at will.

Two-rate meters constructed according to this invention are made to act by indicating the consumption on two different sets of dials, one of which registers the consumption during the low or nominal rate period and the other during the high-rate period. The meter itself consists of two clocks, which are timed both to each other and to normal time. One of the clocks runs always at normal time and the other is arranged so as to be retarded or accelerated by the influence of the current to be metered, as in the ordinary Aron meters. The pendulum of the electrically-affected or electrically-regulated clock carries a coil of fine wire connected as a shunt to the circuit to be measured. The pendulum vibrates in proximity to a coil of wire arranged in the circuit through which the current to be measured passes, and the magnetic influence between these coils when current is being consumed retards or accelerates the pendulum correspondingly and alters the rate of the clock with respect to the normal clock.

At a convenient point between the two trains of wheels of the two clocks a differential-gear arrangement is inserted to connect the two trains, (this also being according to the method usually employed in energy-meters of the Aron type,) so that only the difference between the motions of the respective clocks is conveyed to and registered by the recording mechanism of the meter.

The relative numbers of teeth in the clock roo and registering mechanism and the sensitivity of the magnetic field are so chosen that the division on the counting-dials correspond to the board of trade units, and hence the meter is direct-reading.

One of the wheels of the normal clock is arranged to drive an axle at such a rate that same rotates once in every twenty-four hours, and this axle has fixed to it a rate-changing dial-plate graduated out into twenty-four equal divisions, each equivalent to one hour, and in conjunction with this single twentyfour-hour dial (which is designed to take the place of the two dials heretofore employed in double-rate meters) I propose to employ adjustable devices for actuating the changing mechanism and fordetermining the length and time of commencement and finish of the period during which the supply of electricity is to be metered at the higher rate, which said devices are considerably simplified by taking advantage of the fact that it has been found in practice that although the times at which the periods of high-rate supply commence and finish very considerably at different periods throughout the year, yet it is not often necessary to alter the lengths of these periods once they have been established.

Figure 1 represents the diagram of a tworate meter embodying an electromagnetic method of changing over the registering mechanism from the one set of recording-dials to the other in accordance with my invention. Fig. 2 is an elevation showing the disposition of the single rotating dial and the adjustable contacts provided in connection with the normal clock, also the arrangement of the electromagnet and armature whereby the differential gear interposed between the two clocks is placed in operative connection with either the high or the low rate recording dials. Fig. 3 shows a vertical section of Fig. 2 upon the dotted line 00, while Fig. 4c is a vertical section of the said figure upon the dotted line 00.

In the arrangement shown in the said Figs. 1 to 4 one of the axles a of the normal clock of an Aron meter is driven so that it makes one rotation only in every twenty-four hours, and it has fixed upon it, so as to rotate bodily therewith, a rate-changing dial-plate b, the face of which is graduated out or divided off into twenty-four equal divisions suitably numbered and corresponding to the twentyfour hours during which the said dial will make its complete single rotation. Also carried upon the said axle and coming in front of the dial is a switch-arm c, which is so constructed and secured to the axle as to be capable of adjustment both lengthwise and also angularly around the said axle and of being secured or locked in such adjusted positions for the purposes hereinafter described. The free end of this switch-arm is provided with a small metallic contact-point a, which is always in electrical contact with. a metallic ring a fixed to but insulated from the dial-plate b and forming one of the terminals of a subshunt-circuit a off the pendulum-shunt or other suitable part of the system, the said subshunt (which may have an inserted resistance a being indicated in the diagram Fig. 1 by the dotted lines, and the pendulum-shunt with the pendulum-coil and resistances are indicated in fine continuous lines at e e a, while the coil carrying the current to be metered, together with the main circuit-wires, are shown in the heavy lines and marked ff. To provide for the adjustment of the switch-arm for increasing and decreasing its length, the same may be made in two parts 6 e", the former being slotted, and the latter is adapted to slide lengthwise on a screw carried on the other part, to which it is fixed by a clamping-nut 6, although any other arrangement of adjustable arm may be used. The outer end of the movable part of the said arm carries a second contact-point a, adapted to be brought into contact with any desired part of a plate or block g, which is of special form and is arranged as the other terminal to the subshuntcircuit a*. The adjustable switch-arm thus serves as a means for bridging the terminals and closing the subshunt-circuit at any predetermined period for the purpose of energizing an electromagnet h, arranged in the said subshunt-circuit and having in connection with it arocking armature h, vibrating between the stops, such as 71 and provided with a counterpoise or balance-weight 7L3, whereby it is moved away from the magnetcoil on the subshunt-circuit being broken. This armature carries an intermediate gearwheel 1', which is always in mesh with a wheel j, driven by the differential mechanism of the clocks at a rate corresponding to the difference between the rates of the normal clock and the electrically-controlled clock.

On the subshunt-circuit being closed when the switch-arm is brought by the rotation of the rate-changing dial with the normal clockaxle a into contact with the terminal g the meter at once commences to record the consumption on the high-rate charge, as the magnet is immediately energized and the armature is attracted in opposition to the balance- Weight, and the intermediate Wheelis carried over from its normal or low-rate position and is brought into gear with the wheel 70, of suitable recording mechanism, provided with a set of pointers and dials which record the variations between the two clocks, and consequently the consumption of current, so long as the subshunt-circuit remains closed; but immediately on the expiration of the predetermined period during which the highrate charge is in force the switcharm is by the continued rotation of the dial and axle (1 taken clear of -the terminal 9, and the subshunt-circuit is thereby broken, whereupon the balance-weight of the armature moves the the latter over in the opposite direction, and the intermediate wheel is taken out of the gear with the high-rate recording-dials and made to drive onto the wheel m of another arrangement of mechanism having pointers and dials m, whereby the consumption of current during the normal or low-rate period of supply is registered. The consumptions of current during the alternate high-rate and low-rate periods of supply, respectively, are thereby automatically and separately recorded or indicated on two distinct sets of dials from which the charges to the consumer are calculated.

The angular adjustment of the switch-arm with respect to the rotating twenty-four-hour dial provides means for determining the time at which the recording of the consumption of current shall be transferred to the high-rate dials, this being effected by setting and fixing the said switch-arm (by means of the nut a opposite or over that particular graduation of the dial which corresponds to the hour when the high-rate charging is to commence, while the period during which the high-rate charge is to remain in force is determined by the length of the terminal g, over which the contact-point at the outer end of the said switch-arm passes in its rotatory movement with the axle and dial a b, it being understood that the subshunt-circuit is closed as soon as the said contact-point comes onto the terminal and is opened or broken again immediately the contact is moved clear. It is therefore obvious that by forming or making up the terminal of a number of parts of varying lengths and by arranging for the adjustment of the switch-arm contact so that it shall move along any particular part of the said terminal provision may be made whereby the length of the high-rate period may be readily altered to suit the requirements of supply companies during any particular part of the year or to conform to variable conditions of consumption peculiar to certain districts. Thus in the meter represented in Fig.2 the terminal is made up of a series of four curved parts gg g g of varyinglengths, these lengths being so fixed that each said part is the equivalent to a certain number of hour subdivisions or graduations on the dial, (the part 9' being equal to, say, two hours, g to three hours, g to four hours, and so on,) and the lengthwise adjustment of the switcharm provides for the contact being set in such a position that in course of the rotation of the said switch-arm with the dial (and at any particular hourof the tWenty-four,determined by the relative positions of dial and switcharm) the contact-point of the latter will come into electrical connection with that part of the terminal Whose length is equal to a certain number of hour divisions or graduations on the dial and corresponds to the duration of the period during which the subshuntcircuit is to be kept closed for retaining the differential mechanism of the meter in gear with high-rate-recording dials.

Having fully described my invention, what I desire to claim and secure by Letters Patent is- 1. In two-rate electricity meters of the Aron or two-clock type, the combination with the two clocks one of which is afiected by the current to be metered and the other of which runs at normal time, of an automatic double-rating or rate-changing device which is worked or controlled by the normal timeclock, substantially as described.

2. In two-rate electricity meters of the Aron or two-clock type, in combination "with the normal time-clock,two sets of registering-dials,'means for driving one or the other set of dials and an automatic adjustable rate-changing switch controlled by the normal time-clock for causing the registering action of the meter to be transferred from one set of recording-dials to the other.

3. In two-rate electricity-meters in which I the registering rate of the meter is changed or the registration transferred from one set of dials to another by an electromagnet-switch mechanism controlled by a clock, the combination with a single clock-driven dial rotating once in every twenty-four hours, of an adjustable switch-arm rotating in unison with said dial, anda series of contacts of different lengths adapted to be engaged, respectively, by said switch-arm according to its adjustment whereby both the times of commencement and finish and also the durations of the different rating periods may be altered as and when required, substantially as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

LEONARD JAMES ARON. Witnesses:

ARTHUR SADLER,- HARRY PRATT. 

